Starting 3rd October 2022, you may receive the below message when trying to authorize (or re-authorize) your Google Drive or Google Photos accounts via older versions of SyncBackPro prior to version V10.2.39.0

Access blocked: SyncBackPro’s request is invalid

Error 400: invalid_request

The reason for the error is that Google has decided to stop accepting authorization requests using the legacy OOB (out-of-band) OAUTH flow.

The deprecation announcement was made back in February 2022

If you are a SyncBackPro V10 user and you are running a version older than V10.2.39.0 then you need to update to the latest V10 version from our website at

If you are running a SyncBackPro version prior to V10 (e.g. V8 or V9) then your only solution is to upgrade to V11 by visiting our upgrade store at Your existing profiles may continue working but authorizing with a Google account will fail unless you upgrade to V10.2.39.0 (or newer).